2,199 research outputs found
On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae
The propagation of cellularly stabilized thermonuclear flames is investigated
by means of numerical simulations. In Type Ia supernova explosions the
corresponding burning regime establishes at scales below the Gibson length. The
cellular flame stabilization - which is a result of an interplay between the
Landau-Darrieus instability and a nonlinear stabilization mechanism - is
studied for the case of propagation into quiescent fuel as well as interaction
with vortical fuel flows. Our simulations indicate that in thermonuclear
supernova explosions stable cellular flames develop around the Gibson scale and
that deflagration-to-detonation transition is unlikely to be triggered from
flame evolution effects here.Comment: 6 pages, 2 figures, to appear in the proceedings of the IAU
Colloquium 192, "Supernovae (10 years of SN1993J)", 22-26 April 2003,
Valencia, Spain, Eds. J.M. Marcaide and K.W. Weiler, Springer Verla
Recommended from our members
Air quality investigations of the Sandia National Laboratories Sol se Mete Aerial Cable Facility
The air quality implications of the test and evaluation activities at the Sandia National Laboratories Sol se Mete Aerial Cable Facility are examined. All facets of the activity that affect air quality are considered. Air contaminants produced directly include exhaust products of rocket motors used to accelerate test articles, dust and gas from chemical explosives, and exhaust gases from electricity generators in the test arenas. Air contaminants produced indirectly include fugitive dust and exhaust contaminants from vehicles used to transport personnel and material to the test area, and effluents produced by equipment used to heat the project buildings. Both the ongoing program and the proposed changes in the program are considered. Using a reliable estimate of th maximum annual testing level, the quantities of contaminants released by project activities ar computed either from known characteristics of test items or from EPA-approved emission factors Atmospheric concentrations of air contaminants are predicted using EPA dispersion models. The predicted quantities and concentrations are evaluated in relation to Federal, New Mexico, an Bernalillo County air quality regulations and the human health and safety standards of the American Conference of Governmental Industrial Hygienists
As novidades da psicopatologia estão no século XIX? O retorno a William James e à sua "teoria das emoções"
Leibnizian, Robinsonian, and Boolean Valued Monads
This is an overview of the present-day versions of monadology with some
applications to vector lattices and linear inequalities.Comment: This is a talk prepared for the 20th St. Petersburg Summer Meeting in
Mathematical Analysis, June 24-29, 201
Full counting statistics of a chaotic cavity with asymmetric leads
We study the statistics of charge transport in a chaotic cavity attached to
external reservoirs by two openings of different size which transmit non-equal
number of quantum channels. An exact formula for the cumulant generating
function has been derived by means of the Keldysh-Green function technique
within the circuit theory of mesoscopic transport. The derived formula
determines the full counting statistics of charge transport, i.e., the
probability distribution and all-order cumulants of current noise. It is found
that, for asymmetric cavities, in contrast to other mesoscopic systems, the
third-order cumulant changes the sign at high biases. This effect is attributed
to the skewness of the distribution of transmission eigenvalues with respect to
forward/backward scattering. For a symmetric cavity we find that the third
cumulant approaches a voltage-independent constant proportional to the
temperature and the number of quantum channels in the leads.Comment: new section on probability distribution and new references adde
Weighted ergodic theorems for Banach-Kantorovich lattice
In the present paper we prove weighted ergodic theorems and multiparameter
weighted ergodic theorems for positive contractions acting on
. Our main tool is the use of methods of
measurable bundles of Banach-Kantorovich lattices.Comment: 11 page
The Effect of Air on Granular Size Separation in a Vibrated Granular Bed
Using high-speed video and magnetic resonance imaging (MRI) we study the
motion of a large sphere in a vertically vibrated bed of smaller grains. As
previously reported we find a non-monotonic density dependence of the rise and
sink time of the large sphere. We find that this density dependence is solely
due to air drag. We investigate in detail how the motion of the intruder sphere
is influenced by size of the background particles, initial vertical position in
the bed, ambient pressure and convection. We explain our results in the
framework of a simple model and find quantitative agreement in key aspects with
numerical simulations to the model equations.Comment: 14 pages, 16 figures, submitted to PRE, corrected typos, slight
change
Radar plots: A novel modality for displaying disparate data on the efficacy of eluxadoline for the treatment of irritable bowel syndrome with diarrhea
BackgroundPatients with irritable bowel syndrome with diarrhea (IBS‐D) experience a range of abdominal and bowel symptoms; successful management requires alleviation of this constellation of symptoms. Eluxadoline, a locally active mixed μ‐ and κ‐opioid receptor agonist and δ‐opioid receptor antagonist, is approved for the treatment of IBS‐D in adults based on the results of 2 Phase 3 studies. Radar plots can facilitate comprehensive, visual evaluation of diverse but interrelated efficacy endpoints.MethodsTwo double‐blind, placebo‐controlled, Phase 3 trials (IBS‐3001 and IBS‐3002) randomized patients meeting Rome III criteria for IBS‐D to twice‐daily eluxadoline 75 or 100 mg or placebo. Radar plots were prepared showing pooled Weeks 1‐26 response rates for the primary efficacy composite endpoint (simultaneous improvement in abdominal pain and stool consistency), stool consistency, abdominal pain, urgency‐free days, and adequate relief, and change from baseline to Week 26 in IBS‐D global symptom score, abdominal discomfort, abdominal pain, abdominal bloating, and daily number of bowel movements.Key ResultsThe studies enrolled 2428 patients. Eluxadoline increased Weeks 1‐26 responder proportions vs placebo for the composite endpoint, stool consistency, abdominal pain, urgency‐free days, and adequate relief. Changes from baseline to Week 26 in IBS‐D global symptom score, abdominal discomfort, abdominal pain, abdominal bloating, and number of bowel movements were greater with eluxadoline vs placebo.Conclusions and InferencesData presentation in radar plot format facilitates interpretation across multiple domains, demonstrating that eluxadoline treatment led to improvements vs placebo across 13 endpoints representing the range of symptoms experienced by patients with IBS‐D.Data presentation in radar plot format can facilitate evaluation of the diverse array of symptoms and outcomes that are relevant to a symptom‐based condition like irritable bowel syndrome with diarrhea (IBS‐D). In 2 Phase 3 trials, eluxadoline treatment improved stool consistency and frequency, abdominal pain, bloating and discomfort, feelings of urgency, global symptom score, and adequate relief. Radar plots provide a visual demonstration of improvements with eluxadoline across 13 endpoints encompassing the diverse constellation of symptoms experienced by patients with IBS‐D.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145265/1/nmo13331_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145265/2/nmo13331.pd
- …